DESCRIPTION: Mammaglobin is a recently isolated, novel protein that is homologous to a family of secreted, ligand-binding proteins found in epithelial tissues. Mammaglobin expression is strictly limited to the mammary gland. Furthermore, mammaglobin mRNA and protein are up-regulated in a substantial proportion of breast carcinoma cell lines and tissues. In this proposal three aims are proposed: first, the basic transcriptional regulatory elements will be identified by comparative promoter deletion and gel mobility shift assays in breast and non-breast epithelial cell lines; second, epitope tagging and creating of anti-mammaglobin antisera will be used to examine the quaternary structure, translational regulation, and potential ligand binding capacity; last, the functionality of the promoter elements identified in the first objective will be tested in a transgenic mouse model system.